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Write the Value ( ^ I × ^ J ) ⋅ ^ K + ^ I ⋅ ^ J . - Mathematics

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Question

Write the value  \[\left( \hat{ i }  \times \hat{ j }  \right) \cdot \hat{ k }  + \hat{ i }  \cdot \hat{ j }  .\]

 

Short/Brief Note
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Solution

\[\left( \hat{ i } \times \hat{ j }  \right) . \hat{ k }  + \hat{ i } . \hat{ j }  \]
\[ = \hat{ k }  .\hat{  k }  + 0\]
\[ = \left| \hat{ k }  \right|^2 + 0\]
\[ = 1^2 + 0 ( \because \left| k \right| = 1)\]
\[ = 1\]

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Chapter 25: Vector or Cross Product - very short answers [Page 33]

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RD Sharma Mathematics [English] Class 12
Chapter 25 Vector or Cross Product
very short answers | Q 2 | Page 33

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